相关疑难解决方法(0)

我试图在Julia中实现一个迭代器,但是当for循环尝试调用时会得到异常start.

这是我得到的(我运行include(...),然后using RDF):

julia> methods(start)
# 1 method for generic function "start":
start(graph::Graph) at /Users/jbaran/src/RDF.jl/src/RDF.jl:214

julia> for x in g
       println(x)
       end
ERROR: `start` has no method matching start(::Graph)
 in anonymous at no file

RDF模块中的函数定义目前如下所示:

function start(graph::Graph)
    return GraphIterator(collect(keys(graph.statements)), nothing, nothing, nothing, [], [])
end

知道我做错了什么吗？